The fact that rare medals are coming up begs the question on if medals work like they do in the anime or the games. 

In the anime, rare medals are unique one-of-a-kind evolving super artifacts from a pre-human civilization that allow a medabot to use medaforce and are what every other medal is based off of. Basically all of them are in the hands of the Medabot Corporation and IIRC they're kept in giant isolation tanks in a maximum security vault that only like two people have free access to. They're not something people just have lying around is what I'm saying here.	

In the games, rare medals don't exist. Or rather, it's more like regular medals don't exist, since all medabots are capable of using medaforce techs and all medals can evolve as well, thus rendering the concept of a rare medal pointless.